Sin A Day

Proof That Syns Used To Be Called Sins!

posted on: May 13, 2017. posted in:

So you've just joined Slimming World. You've been to your first ever meeting. And you're both excited and impressed by the science of "Syns", those little things you find in your food that make you gain weight.

You ask your consultant,"what exactly are Syns?" and she replies...

"The word ‘Syns’ is short for ‘synergy’ and reflects the many ‘synergystic’ effects of Slimming World’s unique methods."

Wow. Ask no further questions. There's clearly some serious science behind this syner-thingy-I-can't-even-pronounce-it method. I'll leave the thinking and the calculating to them. They're the brains here, not me.

Soon enough you're avoiding avocados because they're high in "Syns", opting instead to snack on curly wurlies because they're lower in "Syns". It seems too good to be true, swapping boring fruit for yummy chocolate and still losing weight. But you don't challenge it or question it, because you're losing weight and loving it. For now.

Behind the scenes lies a much darker story.

No science. No evidence. No research.

Just a company that stumbled across a word that is now making them millions. A word that is every slimming company's ultimate weapon for both increasing sales of their own products whilst eliminating the competition.


Let's go back in time to the 20th century.

Slimming World was launched back in 1969 by Margaret Miles-Bramwell, who still owns the company to this day. What started with one meeting in Derbyshire soon grew to 1000s of weekly meetings across the UK.

Slimming World was marketed as a more generous alternative to Weight Watchers, helping their members lose weight without giving up the foods they love. It's a familiar business formula...

Help people lose weight, eating whatever they like, and their money is yours.

The problem?

You can't lose weight eating whatever you like. You need what scientists call a "caloric deficit", which is a shortage of calories that forces the body to burn fat. In other words, you need to EAT LESS than your body burns. And eating less is hard. Which is why slimmers will pay thousands of pounds to slimming companies to help them do it.

Slimming World's strategy for eating less?

Enjoy a "Sin-A-Day", with "Sins" being a random list of higher calorie, higher fat foods, as laid out in their old eating manual.


Back then the science was simple. By eating less "Sins" you eat less calories. And by eating less calories you create a "caloric deficit" and lose weight.

So "Sins" became the buzzword of every Slimming World member. But not just a buzzword. A word that put fear and guilt and shame into the members' choices. It was less about eating whatever you want and losing weight, and more about being allowed to eat whatever you want, whilst subtly being made to feel GUILTY and ASHAMED for eating "Sins".

It's a very clever, but mentally damaging trick.

"Eat whatever you want on our plan. You can even eat 'Sins' like cake and chocolate! But we'll make you feel so guilty and ashamed for eating them that you won't want to eat them. Therefore you'll lose weight thinking you can eat whatever you want, when really you're not eating whatever you want. We're controlling your choices with negative language and guilt."

Think about it.

If you were given a choice to eat a food labelled "Free" or a food labelled a "Sin", which are you going to gravitate towards if eating better is your goal? And how are you going to feel if you did eat a "Sin"?

So members lived in fear of "Sins". They therefore ate less of them. Entered a "caloric deficit". And they lost weight. Which, you would think, is Slimming World doing its job.

The reality was very different.

Members reported feeling huge amounts of GUILT and SHAME around food. More guilt than they had before they ever joined Slimming World. People who once ate a chocolate bar and felt relaxed about it, but now felt like they were "Sinners".

This shameful, guilt driven language became a trigger for binge eating. 

"Oh no! I've eaten a Sin! I'm such a bad person! I've ruined my diet! It's ok, I'll just binge for the rest of this week and start fresh next Monday."

This triggered a cycle of starving and binging that was making Slimming World members FATTER, not slimmer. All because of the psychology around the word "Sin".

Slimming World had to take action. The pressure to remove the word "Sin" had become too great, so in the late 1990s they began that process. Gradually phasing out the word "Sin" from their literature and meetings.

Then, in the early 2000s, someone at Slimming World (we don't know who), had the brainwave of the century. They came up with the idea to change the word "Sin" to "Syn", and suggest that the word "Syn" stood for "Synergy".

This one letter change, an 'I' for a 'Y', literally transformed the company.

They not only satisfied their members' demands to remove the negative, binge inducing language of "Sins", but they also made what were once "Sins" sound more credible and scientific by changing them to "Syns". 

Slimming World had gone from a "slimming club"...

To a scientific...


The new credible, scientific brand triggered an increase in their membership that was so huge that they are now the largest slimming club in the country. Larger than Weight Watchers, and now even recommended and paid for by our NHS.

All because they changed "Sins" to "Syns".

They made a guilt driven word, sound like a sciencey word. They took off their religious zealot gowns, and replaced them with white lab coats.

But it gets worse. So much worse.


New members flooded to Slimming World meetings after the name change. And these new members didn't have a clue that "Syns" used to be called "Sins". They thought "Syns" was some kind of new science, so they kept asking the same question in meetings. A question that is now almost like the Slimming World catchphrase.

"How many Syns...?"

Every desperate new member, desperately trying to lose weight, wanted to know the "Syn value" of every single food. Because they believed that "Syns" were a thing, found in food, that made them fatter. If they could know "how many Syns" were in every single food, they could avoid these fattening foods and lose weight.

But what was the magic formula?

How did Slimming World calculate Syns?

At this point Slimming World should have come clean.

"Sorry, but 'Syns' aren't actually a thing. They were treats and high fat foods like chocolate or avocados, that we called 'Sins' to make you avoid them. We change the word to 'Syns' because of pressure from our members, but there's not actually any science behind them. They're just randomly selected treats and high fat foods!"

Did they?

Of course not.

The cash signs rolled up in their eyes, and they realised that the pseudoscience of "Syns" could be used to make huge amounts of money. And over the last 15 years that's exactly what they've done, cashing in on the hype around the made up concept of "Syns".

1. They created a database of foods that list all their "Syn values". 

Which you PAY FOR.

2. They invite food companies to list their products on that database.

Which they PAY FOR.

3. They have a "Syn Hotline" you can call to find out "Syn values".

Which you PAY FOR.

4. They've created their own range of "Low Syn" diet products.

Which you PAY FOR.

5. They penalise competitor products by ranking them "High Syn".

So you PAY FOR theirs instead.

Yes, Slimming World is a company and all companies have the right to maximise their profits. But should they be allowed to profit from the nutritional miseducation of a nation?

If you ask any nutritionist or food scientist to analyse the foods listed on their database, they will find no scientific formula or nutritional correlation as to why some foods are "High Syn" and some foods are "Low Syn". What they'll find is that that what makes a food high or low "Syn" is entirely down to the discretion of Slimming World.

In other words.

They make it up.

Porky Lights discovered this to devastating effect this year, when Slimming World decided to increase the "Syn value" of their sausages. Slimming World even fabricated lab results, which was exposed on the BBC's One Show. And why would they go to such great lengths to increase the "Syn value" of a sausage? Why pick on a small family run sausage company?

Because Porky Lights sausages were out-competing their own brand of "Low Syn" sausages. But with a little tweak to the Porky Lights sausage "Syn value", and then removing them from their database, they could eliminate their competition.

When asked to provide screenshots or other evidence of their so-called "lab test results", Slimming World refused to share them for "legal reasons". Yet another lie from a company that is built on the lie that the "Syn".

So it is clear...

Slimming World make up what is "High Syn" or "Low Syn" to influence their members away from their competitors products towards their own.

But surely "Syns" should be CONSISTENT with the nutritional content of the food, rather than the whim of a company that has no background in nutrition whatsoever? A company that will change the "Syn value" of a food at a moment's notice to protect their profits, but claim it is to "protect their member's weight loss".

The made up, fairytale word "Syn", a word that was discovered through sheer fluke, changing an 'I' for a 'Y', is probably the most valuable word in the slimming industry right now. Which is why Slimming World have not only trademarked "Sin", "Sins", "Syn", "Syn Free", but are also taking anyone to court who uses it.

Sin & Slim for using the word "Sin" in their name.

Julie Goodenough for launching her No! Sins Cafe.

Asda for claiming their ready meals were "Syn free".

A spokesperson for Asda hit the nail on the head.

"Recent information has come to light indicating that the method used by Slimming World to assess whether a ready-meal is free or not, surprisingly, is partly subjective and involves more than simply making food with free ingredients."

In other words.

They make it up.


Let's just take a moment to recognise what's going on here.

We have company that has made up the word "Syn", with no nutrition or scientific basis whatsoever, that is now the country's leading authority on weight loss, paid for by our NHS and our taxes. And who has ZERO EVIDENCE to prove the results of their "Syn" based diet plan brings results beyond 5 years. In fact, most people regain the weight and 40% end up even heavier.

This is a scam on a global level, as Slimming World now pushes to enter the US market, convincing more unsuspecting slimmers that "Syns" are something that float around in their food and cause them to gain weight.


Anymore than unicorns, or pixies or dragons.

So this is what I am kindly asking you to do. 


With family, with friends, with other Slimming World members. And ask them to put the pressure on Slimming World to enter a public debate with Rebelfit to refute these claims. Or just ask them...

"What is the nutritional basis of a syn?"

There isn't one. They won't answer. And as history has shown us, when you ask them this question they'll try to get you banned from Facebook, as they did to me last year. Or they'll block you from Twitter as Dr Jacquie Lavin did to us last year.

And what does that tell you?


p.s. Slimming World, if you're reading this which I know you will be, why not give a public response on your fan page to refute these allegations? Why not share with your members a simple and clear description of the nutritional basis of a "Syn"? Because if you don't, it proves everything we're saying here is true.

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